91891 ÷ 8 = 11486 R3
We're going to perform division on 91891 with 8 as the divisor.

Step 1:
8 goes into 9 1 times with a remainder of 1.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 8 from 9 to get 1.
Bring next digit (1) of the dividend behind the 1 and repeat the process: 11 / 8

Step 2:
8 goes into 11 1 times with a remainder of 3.
Write down 1 as next digit of of the result. 
Result so far: 11
Subtract 8 from 11 to get 3.
Bring next digit (8) of the dividend behind the 3 and repeat the process: 38 / 8

Step 3:
8 goes into 38 4 times with a remainder of 6.
Write down 4 as next digit of of the result. 
Result so far: 114
Subtract 32 from 38 to get 6.
Bring next digit (9) of the dividend behind the 6 and repeat the process: 69 / 8

Step 4:
8 goes into 69 8 times with a remainder of 5.
Write down 8 as next digit of of the result. 
Result so far: 1148
Subtract 64 from 69 to get 5.
Bring next digit (1) of the dividend behind the 5 and repeat the process: 51 / 8

Step 5:
8 goes into 51 6 times with a remainder of 3.
Write down 6 as next digit of of the result. 
Result so far: 11486
Subtract 48 from 51 to get 3.

The final result is 11486 with a remainder of 3.